After upgrading to Pro any counters I have with icon prefixes still display fine on the page but cause the entire page to fail to load, save, or save-as-template in cornerstone.
Similar to what is described at the bottom of this thread I had placed the icons in the number prefix field for the counters which worked fine previously. An example of what I placed in that field:
I’ve recreated this issue in multiple unrelated Pro environments so it should be easy for you to recreate in your own sandbox environment.
I need icons as counter number prefixes for a number of the sites I had developed in X which are now Pro and also need the ability to update the pages they are on.